Hey guys, as the title states. Let me know what you guys are running for muffler and presilencer. 3.5inch. It's a half bridge with sxe366. The car is new to me. Thank you all in advance.

Thank you,
Jose Nieves

 

I would run a high flow 3.5" Borla in the midpipe and maybe a second in the exhaust.

Also, are your wastegates plumbed into the Downpipe or open dump? If open, the first thing I would do is have the wastegate plumbed into the DP.

 

Right now its open, no midpipe muffler. I plan on making an exhaust for her. 3.5 inch and routing wastegates back into the downpipe. I have never had a half bridge engine so this one is very loud.

 

I just went through this and bought an XR-1 mid muffler after trying a different catback. https://www.borla.com/products/xr-1-raceline-400371
This is THE solution as other resonators are more prone to being blown out prematurely, it quiets down the car significantly at idle but still screams and is free flowing at high RPM. It's a straight through design with perforated tubes for sound deadening, there are no plate baffles.

Did you buy the car from Justin?

 

I did, how did you know? Are you familiar with Justin and the car? I have ran the borla xr1 in the past and it has loud
I just took notice that these are rotary specific mufflers now! My last bout with xr1 was 15 years ago where they had a v shaped divider inside.

I also need 3.5 inch, I didn't find the rotary specific borland xr1 in that size

 

SP Mufflers out of Australia makes great stuff.

https://spmufflers.com.au

Their resonators and rear muffler are some of the biggest and quietest that will fit under an FD. I have them on my semi peripheral port, bridge ported 13B with a 3.5" exhaust that I am finishing up.

 

I met him last year after I found out he moved into my neighborhood, he sold the car because he was moving and right before he left I helped him with his caddy.

The rotary XR-1 only has a 3" in/out option, I don't think you'll be losing anything to reduce to 3" for the mid muffler, especially if you are open WG. If you want to see pics of what it looks like looking through shoot me a PM.

 

W
How much did they cost you shipped to the USA?

 

I planned on routing the waste gates back into the downpipe. I've never tested 3.5 downpipe into 3 inch resonators before for flow and hp.

I'm sure someone on this forum has for high boost.

I'm also wondering about the Racing Beat Universal mufflers........

 

You could do a 3.5" DP, and a reducer to 3" for the mid-pipe back.

 

I'm 4" all the way from the turbo back with recirculated wastegates. I'm using a 2 Burns Stainless race mufflers that are 4" in and out as resonators. 1 12" just off the DP and 1 17" at the end of the mid pipe. Sounds very reasonable. Quality is excellent of course and they are completely rebuildable. They now have a "Quite" version of there race mufflers. Pretty much every piping diameter you can think of as well as different overall diameters as well.

 

You have any photos or a youtube of the dyno? Would like to hear and see your setup. I was planning on going 3.5" all the way out.

Did you use a 3-4" expander off of the turbo hotside?

 

I do not have any dyno videos of this setup. Here are some photos. They would be better if the car was on a lift but this is the best I have. Off the turbine it's a 4.21" Marmon V-Band Turbine Outlet Flange to 4" tube adapter. I'm using a normal Vibrant 4" inlet muffler at the rear.

 

That looks great!

 

Thanks, I may be hitting the dyno in a few weeks. I'll try to get a video for you so you can hear the sound. In my opinion sound at idle and cruising at high speed on the freeway are the most important areas for sound. Idle because I'm old and my neighbors/family get annoyed. Freeway because a heavy loud drone annoys me!

I'm definitely going to switch to the burns quite version next time I get some fab work done, just to see the difference.

 

I think we have the same S366 turbo. Do you have a photo of your hotside? I thought that even with a 1.0 A/R housing the outlet was limited to 3"? I thought I Was pushing it going from 3" to 3.5". Would love to see how you got to 4.21".

And I am going to message you about your build. I am shooting for similar HP as yours. Would like to chat about your setup.

 

I'm currently using the new SXE which is quite a bit more turbo then the older S366. My sig is from 2015. I have made close to 700whp on the newer 9180SXE (S366) but I really do not care much for high power numbers at this point. This is on a dynapack hub dyno. Don't fall into the trap of comparing dyno numbers with other dynos. They are just tuning tools. Here is a pic of the DP bare. My turbo placement is quite a bit different then most since I do not have the factory water pump housing and have a ton more room.

I believe this is the adapter my fab guy used. https://agpturbo.com/4-21-marmon-v-b...3-5-or-4-tube/

 

I forget, but it wasn't a lot and arrived pretty quick (~a week).

1 AUS = $0.67 so it was a pretty easy decision to me. Plus you can get their mufflers with any in/out diameter.

 

I’d be reluctant to run the quiet version on a rotary, you’re flowing 30% more exhaust gases per HP than a piston engine and as they openly admit, a 500 hp LS V8 loses 25 hp with a pair of them. Coupled with a BP or PP intake setup being less tolerant of emap (if you have that). The only justification in my mind is if you’re on a track with a strict low sound limit and you’re coming up a dB or two short.

I believe Coast Fabrication in Costa Mesa was the originator of those mufflers but not sure if they’re still in business any more.
.

 

the piston engine (and Mazda's) rule of thumb is about 2.2 CFM per HP
the JDM tuners were more like 3 CFM per HP
CFM per Sq inch of pipe is about 115

so for 500hp you need either a 3.5" or 4" diameter

 

my advice is to not restrict it back to a 3” size with that “quiet” added 2nd stage version muffler.
.

 

Coast fab, the original producers of these mufflers sold that business to Pro Fabrication.

I have tried a few combination of these 3.5" setups. One common thing about all these is the nice tone, no matter how loud they are. They really quiet down some of the annoying frequencies. I did not dyno each iteration so not sure how much power was lost utilizing the 2-stage mufflers. End of the day, this is all a compromise.

-1x single 2-stage quiet muffler in the rear. Too loud for me.
-1x single stage under the car, 1x single stage at rear. Better, but still wanted to quiet it down.
-1x single stage under the car, 1x 2-stage at the rear. MUCH much quieter with the best tone.

I've even considered adding another single stage to the setup however after swapping in a metallic cat for street usage, this was the sweet spot. Use the cat on the street, swap in the single stage for track usage. Expensive, however cry once and get it done: https://www.rx7club.com/market/1158570

 

I have always like the oval magnaflow mufflers and they are pretty quiet but i just switched to the oval borla xr1 and they are even better and very reasonably priced
i went from 3.5” to 4” and the car is reasonably quiet…

i have a resonated oval midpipe with the xr1 and currently the magnaflow 3.5” oval as my tailpipe but i will be switching to the 4” oval xr1 as my tailpipe. I am happy with it

 

Been using them for about the last 18 years, they are quieter still with the packing from Germany I posted up somewhere on here recently.
.

 

I've been considering AES out of Australia. They get good reviews for being quiet on the aus forums and I got to hear the Neal Aderley's 3-rotor at deals gap was reasonably quiet for a 4" exhaust (rear AES muffler with I'm not sure kind of mid-muffler).

Jack.